To dovetail on your comment a bit, my experience has been that fear about not having enough money (and, therefore, going after more of it) has more to do with the person than the amount of money they earn. Greedy people are greedy whether they make $60,000/yr or $6,000,000/yr. They simply have to have more. Others are content making whatever they make, as long as they're getting what they want out of life (which usually doesn't revolve around money as much).

My wife and I wish we made more, at least to cover the cost of rising oil and food prices, but when we take a step back and realize we can pay our bills, afford a few of the little things we want, and have some left to give to charity, we feel very blessed. And that's a feeling no amount of additional money can buy.